Pipe-threading machine.



D. C. WALTER.

PIPE THREADING MACHINE.

APPLICATION FILED MAY 1'0. 1915;

Patented Sept. 14, 1915.

2 SHEETS-SHEET I I INVENTOR. M Q. m

D. C. WALTER.

PIPE THREADING MACHINE.

FILED MAYIO 191 APPL 5. 1 153 .35. PatentedSept. 14, 1915.

2 SSSSSSSS HEET 2.

DAVID C. WALTER, OF TOLEDO, OHIO, ASSIGNOR OF ONE-HALF TO CHARLES J. REUSCHER, OF TOLEDO, OHIO.

PIPE-.THREADIN G MACHINE.

Specification of Letters Patent.

Patented Sept. 14, 1915.

To all whom it may concern:

Be it known that I, DAVID C. WALTER, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have invented a certain new and useful Pipe-Threading Machine; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

This invention relates to thread cutting machines, and particularly to those of the tapered thread cutting type.

The object of my invention is the provision, in a machine of this character, of improved means of a simple and efiicient nature which is automatically operable to eifect a gradual radial adjustment of the chasers during a thread cutting operation, whereby the thread is cut in tapered form.

A further object of my invention is the provision of an improved chaser oiling means, which is automatically operable during a turning of the die carrying head to intermittently drop oil onto the work at the point of cut.

Further objects and advantages of the invention will be apparent from the following detailed description of the same.

The invention is fully described in the following specification, and while, in its broader aspect, it is capable of embodiment in numerous forms, a preferred embodiment thereof is illustrated in the accompanying drawings, in which,-

Figure 1 is a plan of the chaser or die-carrying end of a machine with parts broken away. Fig. 2 is a central sectional view thereof on the line 00, w in Fig. 1. Fig. 3 is a plan of the work holding end of the machine. Fig. 4 is an inner side view of the die carrying head with the lead screw part and oil reservoir closing parts removed therefrom and with parts broken away. Fig. 5 is a perspective view of the lead screw and oil reservoir covering parts.

Fig. 6 is a sectional view of the drip valve associated with each oil reservoir, and Fig. 7 is a perspective View of the grooved shaft and pinion of the chaser adjusting mechamsm.

Referring to the drawings, 1 designates the body portion of the chaser carrying head, which is provided through its center w1th a work receiving opening 2 and has its lnner side provided, in the present instance, at opposite sides of the opening 2 with pockets or recesses forming oil reservoirs 3. The outer-side of the head 1 is provided with a series of radially disposed recesses in which chasers 4 are mounted for radial movements with their cutting ends projecting into the opening 2. A collar 5 is fixedly secured by screws 6, or in any other suitable manner, to the outer side of the head 1 at the inner edge thereof and serves to partially close the outer sides of the grooves or recesses in which the chasers are mounted. A chase"; adjusting plate 7 of annular form is disposed fiat against the outer side of the head 1, being mounted for turning movements on the collar 5 and held to the head by an annular flange 5 of the collar overlapping its inner edge, as best shown in Fig. 2. The plate 7 is provided in its inner side with an eccentric or cam groove 8 for each chaser 4 and adapted to receive a stud 9 projecting from a side of the registering chaser, as shown in Fig. 1. It is apparent that a turning of the plate 7 relative to the head 1 will cause an inward or outward adjustment of the chasers depending upon the direction in which the plate is turned. A handle 10 projects radially from the plate 7 at the outer side thereof to facilitate a turning thereof.

A friction-band 11 is preferably adjustably clamped to the outer peripheral edge of the adjusting plate 7, said band being retained to the plate, when mounted on the head 1, by reason of the plate and band having interengaging annular tongue and groove portions, as best shown at 12 in Fig. 2. The friction-band 11 is split, as at 13, (Fig. 1) and has its ends formed with outwardly extending lugs 14 for receiving a tightening bolt 15, whereby the ends of the band may be drawn together to cause the band to firmly grip the plate 7. The bolt 15 is preferably provided with a thumb nut 16. In order that the lugs 14 at the ends of the band 11 may project a minimum distance from the band and at the same time permit a sufiicient spacing of the nut 16 from the band to facilitate a turning thereof, the split between the ends of the band is disposed in screw sleeve 17, in the present instance, is

shown as comprising a separate piece from the head 1 and as. having flanges 19 projectingtransversely from its inner end in position and of suitable size and shape to fit over and close the open ends of the oil reservoir 3 in the head. The sleeve 17 and its wings 19 are secured to the head 1, in the present instance, by screws 20, which are in- I serted through apertures in the outer edge portions of the flanges 19 and screw into the head.

The work-holder 18 is provided at itsinner end'portion with an annular groove or race-way 21 in which a collar 22 is mounted for free rotary movements. One wall of the groove or race-way 21 is in the form of a nut, which facilitates a mounting of the collar 22 on or a removal of the same from the holder member 18. The collar 22 is anchored against. rotation relative to the chaser carrying head 1 by a screw 23, which is extended loosely through the collar 22 and threads at one end into a registering socket in the head 1, as shown in Fig. 2.

The collar 22 has a boss or arm 24 radially projecting therefrom and provided with an opening 25 in parallel relation to the axis of the head 1. A shaft 26, which is rotatably carried by the head 1 in parallel relation to its axis, as hereinafter described, has one end projecting from the inner side of the head and extending into the opening 25 in the collar arm 24 for both radial and axial movements therein. The portion of the shaft 26, which extends from thehead 1 and into the opening 25 is provided, in the present instance, in its circumference with two grooves 27 and 28, the former being of spiral form and the latter straight with respect'to the longitudinal axis of the shaft. Each of these grooves at the inner end thereof is provided with an offset 29 for the purpose hereinafter described. A screw 30 is threaded through the wall of the opening 25 and the inner end is adapted to project into either groove 27, 28, which is in register therewith, as it may be desired to cut a tapered or straight thread. A. plate 31 is secured to the grooved end of the shaft 26 at the outer side of the arm 24 and is larger in diameter than the shaft 26 to adapt it to coact with the arm 24 and act as a stop for limiting the outward movement of the shaft 26 relative to the cutter arm 24.

A pinion 32 is fixedly mounted on the shaft 26 at the outer side of the head 1 and cooperates with a flange 33 on the shaft to engage the head 1 and prevent axial movements of the shaft relative thereto. The pinion 32 meshes with a segmental rack 34 on the outer periphery of the friction band 11 so that any turning of the shaft 26 will communicate rotation to the band 11 and chaser-adjusting plate 7 to which it is attached. It is apparent that when the screw 30 is in engagement with the spiral groove 27 of the shaft 26 and the head 1 and workholder 18 are relatively turned to cause a movement of one toward the other, the screw 30 will move in the slot 27 toward the inner end thereof and effect a turning of the shaft and pinion 32 and a consequent turning of the chaser adjusting plate 7 and a radial adjustment of the chasers. The head bearing for the shaft 26 is preferably provided partly in the head 1 and partly in a cap 35, which is clamped to-the head by screws 36, or in any other suitable manner. It is preferable in practice to shim the cap 35 out from its seat 011 the head 1 by the use of thin shims, which, as wear occurs in the bearing part, may be removed to compensate there- 37 designates a slide plate which is mount--.

ed for sliding movements in a radial groove in the collar arm 24 to adapt it to be moved into and out of engagement at its inner end with a notch 38 in the registering flange of the collar race-way 21 (seeF igs.-1 and 3). When the plate 37 is in locking engagement with the notch 38 the head 1 and workholder 18 are prevented from relative turning movements, thereby adapting them for use on work which is held by a separate vise or holder-part. In such case the die and work-holder turn as a unit around the work.

Each oil reservoir 3 has an opening 39 in its outer peripheral wall and an axially registering tapered feed opening 40 in the inner wall thereof in position for the oil to drop on the work slightly in advance of the point of cut of the chasers. A needle-valve 41 is projected through the outer opening and'is adapted to seat at its inner end in the drip opening 40 to regulate the quantity of feed of oil therethrough. The portion of the needle-valve stem, which is dlsposed within the outer opening 39, is enlarged, as at 42, and threaded in said opening, and such enlargement without said opening is provided with a knurled head 43 to facilitate a hand turn} ing of the valve. The enlargement 42 is provided longitudinally thereof from its outer end to near its inner end with a socket 44 having a restricted passage 45 leading from its inner end to the interior of the oil reservoir. A valve 46, preferably of ball type, is disposed within the inner end portion of the socket 44 and is retained therein for free limited movements by a plug 47 that is screwed, or otherwise suitably secured, in the outer end of the socket 4 4. This plug has a passage 48 lengthwise therethrough for opening communication between the atmosphere and the portion of the socket 44 in which the valve 46 is disposed. The ball 46 is adapted to seat by gravity in either end of the chamber in which it is disposed and when seated at the end of said chamber closes the air inlet passage 48. During a turning of the cutter head, which usually takes place in a vertical plane, the valve 41 turns therewith, and when such valve is at the upper portion of its turning movement the air valve 46 is so disposed as to permit air to enter the closed oil reservoir 3 to overcome any vacuum which may occur therein by reason of the feeding of oil therefrom, and when the valve 41 is at the lower portion of its revolution the air valve 46 automatically closes the air passage 48 and prevents the outward flow of oil from the res ervoir through the air admitting passage.

The operation of my improved machine is as follows: In adjusting the chasers to suit the size of the work to be acted on the friction band 11 is first loosened with respect to the plate 7 and the plate then turned a desired extent relative to the band 11 to properly adjust the chasers for the initial cutting operation. This having been done the band 11 is tightened to the plate 7 by a tightening of the binding bolt 15, and the operator then turns the cutter head around the work to cut the thread. The turning of the die head relative to the work-holder 18, which is fixedly clamped to the work in any suitable or convenient manner, as is well understood in the art, causes the head and holder to gradually approach each other due to the lead screw connection therebetween. Should the screw 30 be in engagement with the spiral groove 27 in the shaft 26 the relative longitudinal movements of the head and holder will cause the screw to travel lengthwise in ,the groove 27 and effect a turning of the shaft commensurate with the pitch of the groove and the distance of travel of the pin therein. This turning of the shaft 26 is communicated. to the band 11 and through it to the chaser adjusting plate 7 through the medium of the pinion 32 and rack 34-, thereby accomplishing the. desired adjustment of the chasers to cut a tapered thread. If the screw 30 is in engagement with the straight groove 28 of the shaft the shaft is held against turning for cutting a straight thread. A movement of the screw 30 into the inner offset end of either groove 27, 28 causes a quick outward throwing of the chasers to release the work.

- It is apparent that the shaft 26 is anchored against axial or longitudinal movements relative to the die head 1 and has &

movements through the opening provided therefor in the collar 22 which has longitudinal movements with the work-holder.

I wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts except in so far as such limitations are specified in the claims.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

\ 1. In a machine of the class described, a work holder, a die carrying head threaded to said work holder whereby said holder and head have to and fro movements when relatively rotated, a collar rotatably carried by said holder and anchored against rotation relative to the head, said collar having an opening through a part thereof, dies movably carried by the head, a die adjusting plate rotatably carried by the head, a friction band adjustably clamped to the peripheral portion of said cam plate and having a segmental set of rack teeth on its outer periphery, a shaft journaled in a side 'of said head with its axis parallel to the head axis and having a circularly arranged series of teeth at one end in mesh with the rack teeth on said friction band, said shaft being held against axial movements relative to the head and having one end extending from the head and rotatably projecting through the opening in said collar, said projected end of the shaft having a spiral groove, a pin projecting through a part of said collar and into said groove whereby the pin and groove will operate to efiect a turning of the shaft when the shaft is moved through said opening, and a member secured to the extended end of said shaft for coacting with the outer side of said collar to limit the movement of the shaft therethrough'in one direction.

2. In a machine of the class described, a chaser carrying head having a recess in the inner side thereof forming an oil reservoir, a lead screw sleeve removably secured to the inner side of said head and having a part at its inner end closing the outer end of said recess.

3. In a machine of the class described, a chaser carrying head having a plurality of recesses in the inner side thereof forming oil reservoirs, and a lead screw sleeve removably secured to the inner side of said head and having flanges projecting from the inner end thereof and closing the outer ends of said recesses.

In testimony whereof, I have hereunto signed my name to this specification.

DAVID C. WALTER. 

